Machine for grinding files



Sept. 4, 1956 F. J. KONKEL MACHINE FOR GRINDING muss 3 Sheets-Sheet. 1

Filed 001.. 28, 1955 INVENTOR.

,W. WW m 0 Sept. 4, 1956 F. J. KONKEL 2,761,251

MACHINE FOR GRINDING FILES Filed Oct. 28, 1955 s Sheets-Sheet :5

I INVENTOR. PEA/v5 KO/VKEL,

MACHINE FOR GRINDING FILES Frank J. Konirel, Newaygo, Mich.

Application October 28, 1955, Serial No. 543,410

3 Claims. (Cl. 51-33) This invention relates to devices for sharpening the teeth of files, and more particularly to an apparatus for grinding the teeth of an arcuate-toothed flat file.

A main object of the invention is to provide a novel and improved apparatus for grinding the teeth of an arcuate-toothed fiat file, said apparatus being simple in construction, being easy to set up for use, and being arranged to firmly hold the file being sharpened in proper position while being further arranged so that the file may be easily and rapidly advanced as its teeth are sharpened.

A further object of the invention is to provide an improved machine for sharpening the teeth of an arcuatetoothed flat file, said machine involving relatively inexpensive components, being relatively compact in size, being relatively light in weight, being easy to adjust so that the sharpening clement thereof has the proper elevation and angle, and being provided with means for dressing the sharpening element of the apparatus whenever required.

Further objects and advantages of the invention will become apparent from the following description and claims, and from the accompanying drawings, wherein:

Figure 1 is a top view of an improved machine for grinding the teeth of an arcuate-toothed flat file constructed in accordance with the present invention.

Figure 2 is a front elevational view of the machine illustrated in Figure 1.

Figure 3 is an enlarged transverse, fragmentary vertical cross sectional view taken transversely through a porapparatus is designated generally at 11 and comprises an elongated horizontal support, shown at 12. The support 12 comprises a relatively flat, narrow, elongated base bar 13 which is mounted on a pair of transverse, generally rectangular brackets 14, 14 of inverted U shape, as shown in Figure 4-, said brackets having rigidly secured to their lower ends the respective transversely extending angle bars 15, 15, said angle bars projecting laterally substantial distances on opposite sides of the base bar 13, providing substantial stability for base 12.

Secured on the base bar 13 at uniformly spaced points thereon are respective transversely extending, generally U-shaped rest members 16, each rest member 16 being formed with a central vertical recess 17 in its bottom portion which engages with an upstanding Stud 18 secured in the base bar 13, as shown in Figure 4, the side portions of the rest member being secured to the base bar by respective bolts 19, 1% extending upwardly through the ice base bar and threadedly engaged in the respective side portions of the rest member 16.

Secured to the top ends of the rest members 16 are the respective transverse stop plates 20, said stop plates being fastened to the top ends of the respective arms of the rest members 16 by machine screws 21, 21, as shown in Figure 4. Each rest member is formed inwardly adajcent its respective side arms with respective vertical bores 22, 22 having centrally apertured top walls 23,. 23, and containing respective vertically movable abutment elements 24, each of which has a reduced shank portion slidably engageable through the aperture in the associated top wall 23.. The abutment elements 24 are biased upwardly by respective coiled springs 25 hearing between the enlarged bottom portions of the abutment elements and the base bar 13, as is clearly shown in Figure 4.

Disposed in the rest members and engaging the top ends of the respective pairs of abutment members 24 is a longitudinally extending rest plate 26 adapted to receive a file 27 thereon, as shown in Figure 4, the file being urged: against the transverse stop plate 20 by the biasing action of the coiled springs 25, whereby the file is held in a stationary position in the rest members 16 until manually moved longitudinally along the elongated support 12.

Secured to a side marginal portion of the base bar 13 is an upstanding bracket member 28, said bracket member having a horizontal base flange 29 which is fastened to the base bar 13 by a machine screw 30, the flange 29 being held against rotation relative to base bar 13 by a pair of pin members 31, 31 secured in the base member 13 and engaging in vertical bores provided in the flange 29 at opposite sides of the fastening screw 30, as is clearly shown in Figures 1 and 2.

The top end of the bracket member 28 is formed with a downwardly and rearwardly inclined arm 32, said arm being inclined downwardly toward the base bar 13 andhaving secured therein a flat resilient leaf spring member 34 having a transverse lower edge formed to lockingly interengage with a groove of the file 27 to be sharpened to hold the file down and to prevent the filefrom moving longitudinally as its teeth are ground by the sharpening element of the apparatus, as will presently be described. A stop arm 35 secured to the top of a transverse rest member 16 located adjacent the bracket 28 is formed with a transversely extending portion overlying the lower marginal portion of the resilient hold-down plate member 34, limiting upward deflection of the lower edge of plate member 34, while allowing sufiicient upward deflection thereof to permit the file 27 to be advanced as required.

Designated at 36 is a vertical upstanding arm having integrally formed therewith a horizontally extending bottom arm 37v which extends across the base bar 13 and which is rotatably secured thereto, as by a vertical shaft 38 secured to arm 37 and extending rotatably through the base bar 13 into a thrust bearing unit 39 secured to the under side of the bar 13, as is clearly shown in Fig ure 3. The thrust bearing unit 39' may be of any suitable construction, and is preferably of the ball bearing type, as illustrated.

As is clearly shown in Figure 3, the upstanding vertical arm 36 is thus rotatably mounted on the base bar 13 and extends laterally thereof. ecured to the end of the horizontal arm portion 37 of member 36 is the outwardly extending, horizontal handle rod 40, said handle rod being, for example, threadedly engaged in the end of the arm portion 37, whereby the arm portion 37 may be rotated around the vertical axis defined by shaft 38 by means of the handle rod 49. t

It wili be noted that the axis of shaft 38 is centered with respect to the rest members 16, so that the sharpening element of the apparatus may be rotated through an arc concentric with the arcuate groove in the file 27 being sharpened.

The vertical arm 36 is formed with a vertical slot 41, and slidably engaged with arm 36 is a saddle-shaped member 42 to which is fastened the spindle support block 43. A horizontal bolt member 44 extends through block 43, member 42 and the slot 41, as shown in Figure 3, the bolt 44 having a circular head portion 45 received in a counterbore 46 provided in the spindle support block 43. The bolt 44 has a reduced threaded end portion 47 on which is engaged a washer 48 and an annular spring cup 49, as well as a clamping nut 50, as shown in Figure 3, the spring cup 49 containing a coiled spring 51 bearing between washer 48 and the end wall of the cup 49. By tightening the nut 50, the bolt 44 is locked in an adjusted vertical position, whereby the members 42 and 43 are likewise locked in said adjusted position.

As will be apparent in Figure 3, the nut 50 is arranged to exert clamping force on cup 49, which is transmitted to the washer 48, and thence to the outside surface of the vertical arm 36.

Designated at 52 is a vertical screw which extends rotatably through the top portion of the arm 36 and which extends adjacent to the slot 41, the screw 52 being threadedly engaged through the bolt 44, as shown in Figure 3. Screw 52 is provided with the enlarged operating knob 53 rotatably engaged on the top of arm 36, the screw being rotatable in said arm to adjust the height of bolt 44 and of the members 42 and 43. Locking nuts 54 and 55 are provided on screw 52, the upper nut 54 being clampingly engageable against the top wall surface of a generally rectangular recess 56 formed in arm 36 adjacent slot 41, to lock the screw 52, and the lock nut 55 further secures said screw in its locked position, whereby the horizontal screw member 44 is held in a desired vertically adjusted position thereof.

The spindle support block 43 may be rotatably adjusted with respect to the saddle member 42, as by the provision of an arcuate slot 57 in the spindle support block 43 through which extends a clamping screw 58 threadedly engaged in the saddle member 52, whereby the spindle block 43 may be locked in an angularly adjusted position with respect to the saddle member 52. A set screw 59 is threadedly engaged through the block 43 and is lockingly engageable with the saddle member 42 to further lock the spindle support block 43 in its desired angularly adjusted position.

Designated at 60 is a spindle sleeve which is rigidly secured in any suitable manner in the arcuate spindle groove 61 of the spindle block 43, the spindle sleeve 60 having axially journaled therein the shaft 62 on the end of which is mounted the conical grinding wheel 63. On the opposite end of shaft 62 is mounted a pulley 64 which is drivingly coupled to a motor pulley 65 provided on the shaft of an electric motor 66, as by a belt 67, as shown in Figure 2, the electric motor 66 being mounted in a suitable manner on the top portion of the block 43. Thus, an upstanding channel-shaped bracket member 67 may be rigidly secured to the block 43, as by being engaged on the block and being fastened thereto by machine screws 68 extending through the flanges of the bracket member and threadedly engaged in the opposite side of edges of the block 43.

As shown in Figure 2, the web portion of the bracket member 67 is formed with an arcuate slot 69 registering with the slot 57 in block 43, through which the clamping screw 58 extends, the set screw 59 extending through an aperture formed in bracket 67 registering with the threaded aperture in block 43 receiving said set screw.

Rigidly secured to the side flanges of the bracket member 67 are the horizontal angle bars 70, 70 on which are secured the motor support plate 71, the motor 66 being supported on the plate 71 and being provided with a hook-like lug element 72 which is lockingly engageable in an aperture provided in the support plate 71, the top portion of the motor being fastened to the top end portion of the bracket member 67 by a pair of coiled springs 73 and 74, whereby the motor is biased in a direction insuring the locking interengagement of the hook element 72 with the aperture in the motor support plate 71.

Obviously, the motor 66 may be suitably fastened in any other desired manner to the bracket member 67, the fastening means for the motor being such that suitable tension is provided for the drive belt 67.

As is clearly shown in Figure 2, the spindle assembly, including sleeve 60 and bracket 67 may be adjusted to the proper height thereof and the assembly may be angularly adjusted around the horizontal pivot axis defined by the bolt 47 to provide the desired orientation of the conical grinding wheel 63 with respect to the teeth of the file 27 to be sharpened. It will be further apparent that the grinding wheel 63 is adjusted to a fixed position, said position being such that the edge of the grinding wheel exerts a force against the file developed by the springs 25, 25 in the rest members 16, since the edge of the grinding wheel is supported in a position to make the required arcuate cut across the file to form the file teeth properly. Thus, the file is held against the edge of the grinding wheel 63 by the force of springs 25, 25 transmitted to the file through the abutment elements 24, 24 and through the rest plate 26.

As each tooth is formed, the file may be advanced to form the next tooth, since the springs 25, 25 and the leaf spring 34 are sufficiently yieldable to allow the file to be manually advanced through the rest members 16 supporting same.

Rigidly secured to the base bar 13 on the side thereof opposite the bracket member 28 is an outwardly projecting arm 75 formed with a vertical sleeve 76 provided with a set screw 77. Designated at 78 is a vertical tool post which is received in the sleeve 76 and locked in an adjusted position therein by the set screw 77. The tool post 78 is provided with a chuck element 79 in which is received a grinding wheel dressing tool 80, for example of the diamond type, said dressing tool being employed to dress the grinding surface of grinding wheel 63 whenever required. Preferably, the bracket member 75 is provided with means clampingly engageable with the base bar 13, so that the bracket member 75 may be adjusted longitudinally along said base bar to a position allowing the dressing tool 80 to engage the grinding surface of grinding wheel 63 Without disturbing the adjustment of the grinding wheel.

In order to insure proper support of the file while it is being sharpened, an auxiliary support block 81 is mounted transversely on the base bar 13 beneath the rest plate 26 and beneath the location of the grinding wheel 63, as shown in Figure 2, the block 81 being provided with spring-biased, upwardly projecting plunger elements 82 similar to the abutment elements 24, 24 bearing upwardly on the bottom surface of the rest plate 26 and supporting said rest plate against excessive downward deflection when the file 27 is engaged by the grinding edge of the wheel 63.

While a specific embodiment of an improved apparatus for grinding the teeth of an arcuate-toothed flat file has been disclosed in the foregoing description, it will be understood that various modifications within the spirit of the invention may occur to those skilled in the art. Therefore, it is intended that no limitations be placed on the invention except as defined by the scope of the appended claims.

What is claimed is:

1. An apparatus for grinding the teeth of an arcuatetoothed flat file comprising an elongated horizontal support, a plurality of generally U-shaped transverse rest members secured on said support in longitudinally spaced relation thereon, said rest members being formed and arranged to receive a file thereon, an upstanding bracket member secured to the intermediate portion of said support, an inclined resilient plate member secured to said support and having a transverse lower edge lockingly engageable with a file supported on the rest members, a vertical upstanding arm rotatably mounted on said support and extending laterally thereof, said arm being formed with a vertical slot, an inclined spindle support slidably engaged with the inside surface of said arm, a horizontal screw connected to said spindle support and extending through said slot, a clamping nut threaded on said horizontal screw adjacent the outside surface of said arm, a vertical screw rotatably mounted in the top portion of said arm and extending adjacent said slot, said vertical screw being threadedly engaged through the horizontal screw, whereby the horizontal screw may be adjusted vertically and whereby the spindle support may be clamped in a vertically adjusted position on said arm, a grinder spindle assembly mounted on said spindle support, said assembly including a spindle sleeve, a shaft journaled in said sleeve, and a grinding wheel secured on the end of said shaft, a motor bracket secured on said spindle support above said spindle sleeve, a motor mounted on said last-named bracket, and means drivingly coupling said motor to said shaft.

2. An apparatus for grinding the teeth of an arcu atetoothed fiat file comprising an elongated horizontal support, a plurality of generally U-shaped transverse rest members secured on said support in longitudinally spaced relation thereon, transverse stop plates secured to the top ends of said rest members, a pair of vertically movable abutment elements mounted in each rest member, spring means biasing the abutment elements upwardly toward the stop plates, an elongated rest plate seated in the rest members and being engaged by said abutment elements, whereby a file supported on said rest plate is urged upwardly against said transverse stop plates, an upstanding bracket member secured to the intermediate portion of said support, an inclined resilient plate member secured to said support and having :a transverse lower edge lockingly engageable with a file supported on the rest plate, a vertical upstanding arm ro-tatably mounted on said support and extending laterally thereof, said arm being formed with a vertical slot, an inclined spindle support slidably engaged with the inside surface of said arm, a horizontal screw connected to said spindle support and extending through said slot, a clamping nut threaded on said horizontal screw adjacent the outside surface of said arm, a vertical screw rotatably mounted in the top portion of said arm and extending adjacent said slot, said vertical screw being threadedly engaged through the hori- 5 zontal screw, whereby the horizontal screw may be adjusted vertically and whereby the spindle support may be clamped in a vertically adjusted position on said arm, a

grinder spindle assembly mounted on said spindle support, said assembly including a spindle sleeve, a shaft journaled in said sleeve, and a grinding wheel secured on the end of said shaft, a motor bracket secured on said spindle support above said spindle sleeve, a motor mounted on said last-named bracket, and means drivingly coupling said motor to said shaft.

3. An apparatus for grinding the teeth of an arcuatetoothed flat file comprising an elongated horizontal support, a plurality of generally U-shaped transverse rest members secured on said support in longitudinally spaced relation thereon, transverse stop plates secured to the top ends of said rest members, a pair of vertically movable abutment elements mounted in each rest member, spring means biasing the abutment elements upwardly toward the stop plates, an elongated rest plate seated in the rest members and being engageable by said abutment elements, whereby a file supported on said rest: plate is urged upwardly against said transverse stop plates, an upstanding bracket member secured to the intermediate portion of said support, an inclined resilient plate member secured to said support and having a transverse lower edge lockingly engageable with a file supported on the rest plate, a vertical upstanding arm rotatably mounted on said support and extending laterally thereof, said arm being formed with a vertical slot, an inclined spindle support slidably engaged with the inside surface of said arm, a horizontal screw connected to said spindle support and extending through said slot, a clamping nut threaded on said horizontal screw adjacent the outside surface of said arm, a vertical screw rotatably mounted in the top portion of said arm and extending adjacent said slot, said vertical screw being threadedly engaged through the horizontal screw, whereby the horizontal screw may be adjusted vertically and whereby the spindle support may be clamped in a vertically adjusted position on said arm, a grinder spindle assembly mounted on said spindle support, said assembly including a spindle sleeve, a shaft journaled in said sleeve, and a grinding wheel secured on the end of said shaft, a motor bracket secured on said spindle support above said spindle sleeve, a motor mounted on said last-named bracket, means drivingly coupling said motor to said shaft, and a grinding wheel dressing tool mounted on one side of said support and being engageable with said grinding wheel.

References Cited in the file of this patent UNITED STATES PATENTS 2,212,999 Faulder Aug. 27, 1940 2,222,034 Jackson Nov. 19, 1940 2,552,164 Foss May 8, 1951 

